Fluorinated diester compounds and their use in heat transfer system

ABSTRACT

A compound of formula (I): wherein W is independently selected from the group consisting of H, F, CI, Br, and I; X is independently selected from the group consisting of H, F, CI, Br, and I; Y is independently selected from the group consisting of F, CI, Br, and I; Z is independently selected from the group consisting of H, F, CI, Br, and I; n is an integer from 1 to 8; and n′ is an integer from 1 to 12.

This application is the U.S. National Phase under 35 U.S.C. § 371 ofInternational Application No. PCT/GB2015/053148, filed Oct. 21, 2015,designating the United States and published in English on Apr. 28, 2016,as WO 2016/063056, which claims priority to United Kingdom ApplicationNo. 1418709.0, filed Oct. 21, 2014, each of which is incorporated byreference in its entirety.

FIELD

The present invention relates to diester compounds and to uses of andmethods of preparing the same.

BACKGROUND

The listing or discussion of information or a prior-published documentin this specification should not necessarily be taken as anacknowledgement that the information or document is part of the state ofthe art or is common general knowledge.

Fluorocarbon-based compounds are currently used in a large number ofcommercial and industrial applications, such as propellants, blowingagents and heat transfer fluids. The interest in and use offluorine-based compounds, particularly (hydro)fluoroolefins, as heattransfer fluids has increased as new refrigerants are sought.

Dichlorodifluoromethane (refrigerant R-12) possessed a suitablecombination of refrigerant properties and was for many years the mostwidely used refrigerant. Due to international concern that fully andpartially halogenated chlorofluorocarbons, such asdichlorodifluoromethane and chlorodifluoromethane, were damaging theearth's protective ozone layer, there was general agreement that theirmanufacture and use should be severely restricted and eventually phasedout completely. The use of dichlorodifluoromethane was phased out in the1990's.

Chlorodifluoromethane (R-22) was introduced as a replacement for R-12because of its lower ozone depletion potential. Following concerns thatR-22 is a potent greenhouse gas, its use is also being phased out.R-410A and R-407 (including R-407A, R-407B and R-407C) have beenintroduced as a replacement refrigerant for R-22. However, R-22, R-410Aand the R-407 refrigerants all have a high global warming potential(GWP, also known as greenhouse warming potential).

1,1,1,2-tetrafluoroethane (refrigerant R-134a) was introduced as areplacement refrigerant for R-12. However, despite having a low ozonedepletion potential, R-134a has a GWP of 1430. It would be desirable tofind replacements for R-134a that have a lower GWP.

R-152a (1,1-difluoroethane) has been identified as an alternative toR-134a. It is somewhat more efficient than R-134a and has a greenhousewarming potential of 120. However the flammability of R-152a is judgedtoo high, for example to permit its safe use in mobile air conditioningsystems. In particular its lower flammable limit in air is too low, itsflame speeds are too high, and its ignition energy is too low.

(Hydro)fluoroolefins, particularly tetrafluoropropenes, have beenproposed as a possible refrigerants for use in a variety of heattransfer devices.

Heat transfer fluids are often used in combination with lubricants, suchas in heating and refrigeration systems. Such lubricants are included inheat transfer compositions to ensure continued smooth operation of theheat transfer system.

It is necessary that lubricants used in heat transfer compositions arecompatible with the refrigerants in the compositions. The compatibilityof the lubricant and the refrigerant is predicated on a number offactors, such as a desire for at least partial miscibility at part ofthe operating temperature range, a low tendency to degrade or react inuse and appropriate viscosities for the application.

There is therefore a need for lubricants that can be used in conjunctionwith heat transfer fluids, both those currently used and those proposedas replacement compositions. In particular, lubricants are desired thatare miscible with a wide range of heat transfer fluids, possess anappropriate viscosity, do not reduce the performance of heat transferfluids and have low flammability; all in addition to successfullyfunctioning as a lubricant.

Lubricants with low flammability are particularly important for heattransfer fluids that are used in automobile air-conditioning, as suchcompositions are in danger of coming into contact with hot metalsurfaces of the engine.

SUMMARY

The subject invention addresses the above and other deficiencies by theprovision of a compound of formula (I):

whereinW is independently selected from the group consisting of H, F, Cl, Br,and I;X is independently selected from the group consisting of H, F, Cl, Br,and I;Y is independently selected from the group consisting of F, Cl, Br, andI;Z is independently selected from the group consisting of H, F, Cl, Br,and I;n is an integer from 1 to 8;and n′ is an integer from 1 to 12.

Also provided by the invention is a composition comprising a heattransfer fluid, together with one or more compounds of formula (I).

Further provided by the invention is a method of preparing a compound offormula (I) comprising reacting a compound of formula (A) with acompound of formula (B):

whereinW is independently selected from the group consisting of H, F, Cl, Br,and I;X is independently selected from the group consisting of H, F, Cl, Br,and I;Y is independently selected from the group consisting of F, Cl, Br, andI;Z is independently selected from the group consisting of H, F, Cl, Br,and I;V is independently selected from the group consisting of Cl and OH;n is an integer from 1 to 8;and n′ is an integer from 1 to 12.

DETAILED DESCRIPTION

Compounds of the Invention

In one aspect, the invention provides a compound of formula (I):

whereinW is independently selected from the group consisting of H, F, Cl, Br,and I;X is independently selected from the group consisting of H, F, Cl, Br,and I;Y is independently selected from the group consisting of F, Cl, Br, andI;Z is independently selected from the group consisting of H, F, Cl, Br,and I;n is an integer from 1 to 8;and n′ is an integer from 1 to 12.

In an embodiment, W and X are independently H or F, preferably H.Preferably, Y is F. Preferably, Z is H or F. Advantageously, n is aninteger from 1 to 5, for example, an integer from 2 to 5. Preferably, n′is an integer from 1 to 10, for example, an integer from 2 to 8, e.g. 3,4, 5 or 6.

In an embodiment of the invention, the compound of formula (I) is acompound of formula (II):

In a further embodiment of the invention, the compound of formula (I) isa compound of formula (III)

In an alternative embodiment of the invention, the compound of formula(I) is a compound of formula (IV)

In an embodiment of the invention, there is a provided a compositioncomprising at least two different compounds of formula (I).

In an embodiment, the value of n is the same for the at least twocompounds of formula (I). Alternatively, the values of n for the atleast two compounds of formula (I) are different.

In an embodiment, the value of n′ is the same for the at least twocompounds of formula (I). Alternatively, the values of n′ for the atleast two compounds of formula (I) are different, such as one value ofn′ being twice that of the other.

In an embodiment, the identity of X, Y or Z may be the same or differentfor the at least two compounds of formula (I). Preferably, the identityof Z may both be H, both be F, or may be H for one of the compounds offormula (I) and F for another compound of Formula (I).

In a further embodiment, there is a provided a composition comprising atleast two compounds of formula (I), wherein at least one compound offormula (I) is a compound of formula (V) and at least one compound offormula (I) is a compound of formula (VI).

The compounds of formula (I) are less flammable than polyalkylene glycol(PAG) and/or polyol ester (POE) based lubricants. Preferably, thecompounds of formula (I) have a lowest temperature of ignition of about500° C. or greater, such as 510° C., 520° C., 530° C., 540° C., 550° C.,560° C., 570° C., 580° C., 590° C., preferably about 600° C. or greater,for example 610° C., 620° C., 630° C. or 640° C.

Advantageously, the compounds of formula have a high degree ofmiscibility with heat transfer fluids, particularly fluorine-based heattransfer fluids.

Preferably, the compounds of formula (I) will have a melting point offrom about −20° C. to about −70° C., such as from about −25° C. to about−60° C., preferably from about −30° C. to about −50° C.

Preferably, the compounds of formula (I) will have a viscosityappropriate for use with heat transfer fluids, such as in refrigerationor air-conditioning devices. Conveniently, compounds of formula (I) withhave a viscosity of from about 20 to about 70 cSt, such as from 25 toabout 65 cSt, from about 30 to about 60 cSt or from about 35 to about 55cSt. Preferably, the compounds of formula (I) will have a viscosity offrom about 40 to about 50 cSt.

The compounds of formula (I) may be further used as heat transferagents.

Compositions of the Invention

In another aspect, the invention provides a composition comprising aheat transfer fluid, together with one or more compounds of formula (I).

In an embodiment, the composition may comprise a heat transfer fluid andone or more compounds of formula (II), (Ill) or (IV). Alternatively oradditionally the composition may comprise at least two compounds offormula (I), for example, wherein at least one compound of formula (I)is a compound of formula (V) and at least one compound of formula (I) isa compound of formula (VI).

In an alternative embodiment, the composition may comprise a heattransfer fluid and a compound of formula (VII).

Preferably, the heat transfer fluid comprises one or more compoundsselected from the group of (hydro)fluoroolefins (HFOs),hydrofluorocarbons (HFCs), chlorofluorocarbons (CFCs),hydrochlorofluorocarbons (HCFCs) and hydrocarbons.

Advantageously, the heat transfer fluid may comprise one or morecompounds selected from the group of 1,3,3,3-tetrafluoropropene(R-1234ze), 2,3,3,3-tetrafluoropropene (R-1234yf),3,3,3-trifluoropropene (R-1243zf), 1,1,1-trifluoro-2-chloropropene(R-1233xf), 1,1,1-trifluoro-3-chloropropene (R-1233zd),1,1,1,2-tetrafluoroethane (R-134a), 1,1-difluoroethane (R-152a),difluoromethane (R-32), fluoroethane (R-161), pentafluoroethane (R-125),1,1,2,2-tetrafluoroethane (R-134), propane, propylene, carbon dioxide,1,1,1,3,3-pentafluoropropane (R-245fa), 1,1,1,3,3,3-hexofluoropropane(R-236fa), 1,1,1,2,3,3,3-heptafluoropropane (R-227ea),1,1,1-trifluoroethane (R-143a), n-butane, iso-butane and1,1,1,3,3-pentafluorobutane (R-365mfc), such as R-1234ze, R-1234yf,R-1243zf, R-134a, R-152a and R-32.

For the avoidance of doubt, it is to be understood that where a compoundmay exist as one of two configurational isomers, e.g. cis and transisomers around a double bond, the use of the term without an isomerdesignation (e.g. R-1234ze or R-1233zd) is to refer to either isomer.

In some embodiments, the heat transfer fluid comprisestetrafluoropropenes. Preferably, the heat transfer fluid comprisesR-1234ze, even more preferably the heat transfer fluid comprisesR-1234ze(E). Advantageously, the heat transfer composition comprisesR-1234yf.

Advantageously, compositions of the invention are less flammable than acomposition comprising the same heat transfer fluid combined with apolyalkylene glycol (PAG) and/or a polyol ester (POE) based lubricant.

Preferably, the compositions of the invention are less flammable thanthe heat transfer fluid alone.

Preferably, the composition of the invention has a lowest temperature ofignition of about 500° C. or greater, such as 510° C., 520° C., 530° C.,540° C., 550° C., 560° C., 570° C., 580° C., 590° C., preferably about600° C. or greater, for example 610° C., 620° C., 630° C. or 640° C.

In an embodiment, the composition of the invention may be non-flammable.

Flammability may be determined in accordance with ASHRAE Standard 34incorporating the ASTM Standard E-681 with test methodology as perAddendum 34p dated 2004, the entire content of which is incorporatedherein by reference.

Conveniently, the Global Warming Potential (GWP) of the compositions ofthe invention may be less than about 3500, 3000, 2500 or 2000. Forinstance, the GWP may be less than 2500, 2400, 2300, 2200, 2100, 2000,1900, 1800, 1700, 1600 or 1500. The GWP of the compositions of theinvention preferably is less than 1400, 1300, 1200, 1100, 1000, 900,800, 700, 600 or 500.

Preferably, the compositions of the invention have zero or near zeroozone depletion.

In an embodiment, the compositions of the invention have improved heattransfer properties than the heat transfer fluid alone.

Without wishing to be bound by theory, it is believed that compounds offormula (I) may further act as heat transfer agents and thereforeincrease the heat transfer properties of the compositions of theinvention.

Advantageously, the composition further comprises a stabiliser.

Preferably the stabiliser is selected from group consisting ofdiene-based compounds, phosphates, phenol compounds and epoxides, andmixtures thereof.

Conveniently, the composition further comprises an additional flameretardant.

Preferably, the flame retardant is selected from the group consisting oftri-(2-chloroethyl)-phosphate, (chloropropyl) phosphate,tri-(2,3-dibromopropyl)-phosphate, tri-(1,3-dichloropropyl)-phosphate,diammonium phosphate, various halogenated aromatic compounds, antimonyoxide, aluminium trihydrate, polyvinyl chloride, a fluorinatediodocarbon, a fluorinated bromocarbon, trifluoro iodomethane,perfluoroalkyl amines, bromo-fluoroalkyl amines and mixtures thereof.

The invention also provides a heat transfer device containing acomposition of the invention and/or the use of a composition of theinvention in a heat transfer device.

In an embodiment, the heat transfer device is a refrigeration device.

Conveniently, the heat transfer device is selected from the groupconsisting of automotive air conditioning systems, residential airconditioning systems, commercial air conditioning systems, residentialrefrigerator systems, residential freezer systems, commercialrefrigerator systems, commercial freezer systems, chiller airconditioning systems, chiller refrigeration systems, and commercial orresidential heat pump systems.

Preferably, the heat transfer device contains a compressor.

According to a further aspect of the invention, there is provided amethod of cooling an article, which comprises condensing a compositionof the invention and thereafter evaporating the composition in thevicinity of the article to be cooled.

According to an another aspect of the invention, there is provided amethod for heating an article, which comprises condensing a compositionof the invention in the vicinity of the article to be heated andthereafter evaporating the composition.

According to a further aspect of the invention, there is provided amechanical power generation device containing a composition of theinvention.

Preferably, the mechanical power generating device is adapted to use aRankine Cycle or modification thereof to generate work from heat.

According to an another aspect of the invention, there is provided amethod of retrofitting a heat transfer device comprising the step ofremoving an existing heat transfer fluid and introducing a compositionof the invention. Preferably, the heat transfer device is arefrigeration device. Advantageously, the heat transfer device is anair-conditioning system.

According to a further aspect of the invention, there is provided amethod of reducing the flammability of a composition by the addition ofone or more compounds of formula (I) to (VI).

Methods of Preparation of Compounds and Compositions of the Invention

The invention provides a method of preparing a compound of formula (I)comprising reacting a compound of formula (A) with a compound of formula(B):

whereinW is independently selected from the group consisting of H, F, Cl, Br,and I;X is independently selected from the group consisting of H, F, Cl, Br,and I;Y is independently selected from the group consisting of F, Cl, Br, andI;Z is independently selected from the group consisting of H, F, Cl, Br,or I;V is independently selected from the group consisting of Cl and OH;n is an integer from 1 to 8;and n′ is an integer from 1 to 12.

In an embodiment W and X are independently H or F, preferably H.Preferably, Y is F. Preferably, Z is H or F. Conveniently, V is Cl.Advantageously, n is an integer from 1 to 5. Preferably, n′ is aninteger from 1 to 10, e.g. an integer from 2 to 8 such as 3, 4, 5 or 6.

Preferably, the molar ratio of compound of formula (A) to compound offormula (B) is at least 2:1.

In an aspect of the invention, there is a method of preparing a compoundof formula (II) comprising reacting pentafluoropropan-1-ol with acompound of formula (B), wherein n′ 4 and W is OH or Cl, preferablywherein W is Cl.

Advantageously, the molar ratio of pentafluoropropan-1-ol to compound offormula (B) is at least 2:1.

In an aspect of the invention, there is a method of preparing a compoundof formula (III) comprising reacting pentafluoropropan-1-ol with acompound of formula (B), wherein n′ 8 and W is OH or Cl, preferablywherein W is Cl.

Advantageously, the molar ratio of pentafluoropropan-1-ol to compound offormula (B) is at least 2:1.

In an aspect of the invention, there is a method of preparing a compoundof formula (IV) comprising reacting 2,2,3,3-tetafluoropropan-1-ol with acompound of formula (B), wherein n′ is 8 and W is OH or Cl, preferablywherein W is Cl.

Advantageously, the molar ratio of 2,2,3,3-tetafluoropropan-1-ol tocompound of formula (B) is at least 2:1.

In an aspect of the invention, there is a method of preparing acomposition comprising at least two compounds of formula (I) wherein atleast one compound of formula (I) is a compound of formula (V) and atleast one compound of formula (I) is a compound of formula (VI), whichmethod comprises reacting 2,2,3,3,4,4,5,5-octofluoropentan-1-ol with acompound of formula (B′), wherein n′ is 4 and W is OH or Cl; andcomprising reacting 2,2,3,3,4,4,5,5-octofluoropentan-1-ol with acompound of formula (B″), wherein n′ is 8 and W is OH or Cl, preferablywherein W is Cl.

In some embodiments, the method is conducted in one-step reaction.Advantageously, the molar ratio of 2,2,3,3,4,4,5,5-octofluoropentan-1-olto the combined amount of compounds of formula B′ and B″ is at least2:1.

Compositions of the invention may be prepared by the method of mixingone or more compounds of formula (I) to (VI) with a heat transfer fluid.

Composition of the invention may be prepared by mixing one or morecompounds or formula (I), prepared through a method of the invention,with a heat transfer fluid.

Preferably, the heat transfer fluid comprises one or more compoundsselected from the group of (hydro)fluoroolefins (HFOs),hydrofluorocarbons (HFCs), chlorofluorocarbons (CFCs),hydrochlorofluorocarbons (HCFCs) and hydrocarbons.

Advantageously, the heat transfer fluid comprises one or more compoundsselected from the group of R-1234ze, R-1234yf, R-1233xf, R-1233zd,R-1243zf, R-134a, R-152a, R-32, R-161, R-125, R-134, propane, propylene,carbon dioxide, R-245fa, R-236fa, R-227ea, R-143a, n-butane, iso-butaneand R-365mfc.

Conveniently, wherein the heat transfer fluid comprises one or morecompounds selected from the group of R-1234ze, R-1234yf, R-1233xf,R1233zd, R-1243zf, R-134a, R-152a and R-32.

Preferably, the heat transfer fluid comprises R-1234ze.

Preferably, the heat transfer fluid comprises R-1234yf.

Examples

Synthesis of Compound of Formula (II)

2,2,3,3,3-pentafluoropropan-1-ol (110 g, 0.73 mol) was charged to a 250mL round bottom flask fitted with a condenser and dropping funnel. Thealcohol was stirred and heated to 40° C. Adipoyl chloride (44.6 g, 0.24mol) was charged to a dropping funnel and added slowly to the alcohol.The mixture was stirred at 40° C. for approximately 4 to 5 hours,allowed to cool to room temperature and then the excess alcohol wasremoved under vacuum. The remaining clear oil was filtered to removeparticulates and then dried over activated molecular sieves. Thereaction gave 78.5 g (78.5% yield) of a compound of Formula (II).

¹H NMR (DMSO): δ 4.74-4.83 (t CH₂), δ 2.41-2.47 (m C₂H₄), δ 1.53-1.62 (mC₂H₄) ¹³C NMR (DMSO): δ 171.21 (s OC═O), δ 120.05 (t CF₂), δ 116.26 (tCF₂), δ 115.39-112.02 (m CF₃), δ 57.79-58.71 (t CH₂O), δ 32.35-32.51 (dCH₂C═O), δ 23.28-23.62 (d CH₂)

¹⁹F NMR (DMSO): δ −6.17-−5.49 (s 6F), δ −47.37-−45.47 (s 4F)

IR: 1764 cm⁻¹ (OC═O), 1197 cm⁻¹ (C—O), 1137 cm⁻¹ (C—F)

TGA: One mass loss is seen giving a boiling range of 240-260° C. Noimpurities

Density: 1.42 g/ml

Viscosity: 7.06 cP

RPM Centipoise (cP) Torque (%) <10 Out of Range Out of Range 10 6.6 1112 6.6 13.2 20 6.78 22.6 30 6.94 34.7 50 7.02 58.5 60 7.06 70.6 100 Outof Range Out of RangeSynthesis of Compound of Formula (III)

2,2,3,3,3-pentafluoropropan-1-ol (96.6 g, 0.64 mol) was charged to a 250mL round bottom flask fitted with a condenser and dropping funnel. Thealcohol was stirred and heated to 40° C. Sebacoyl chloride (51.3 g, 0.21mol) was charged to a dropping funnel and added slowly to the alcohol.The mixture was stirred at 40° C. for approximately 4 to 5 hours,allowed to cool to room temperature and then the excess alcohol wasremoved under vacuum. The remaining clear oil was filtered to removeparticulates and then dried over activated molecular sieves. Thereaction gave 40.9 g (40.9% yield) of a compound of Formula (III). Theyield is lower than expected due to inadvertent loss of product beforeweighing.

¹H NMR (DMSO): δ 4.73-4.82 (t CH₂), δ 2.37-2.42 (t C₂H₄), δ 1.50-1.55 (mC₂H₄), δ 1.24 (s C₄H₈)

¹³C NMR (DMSO): δ 171.43 (s OC═O), δ 120.06 (t CF₂), δ 108.69-116.27 (mCF₃), δ 57.74-58.46 (t CH₂O), δ 32.77 (s CH₂C═O), δ 27.97-28.44 (mC₂H₄), δ 24.02-24.36 (d C₂H₄)

¹⁹F NMR (DMSO): δ −8.98-−8.29 (s 6F), δ −48.29 (s 4F)

IR: 1764 cm⁻¹ (OC═O), 1197 cm⁻¹ (C—O), 1149 cm⁻¹ (C—F)

TGA: One mass loss is seen giving a boiling range of 280-310° C. Noimpurities

Density: 1.31 g/ml

Viscosity: 10.51 cP

RPM Centipoise (cP) Torque (%) <10 Out of Range Out of Range 10 10.0816.8 12 10.10 20.2 20 10.26 34.2 30 10.40 52.0 50 10.51 87.6 60 Out ofRange Out of RangeSynthesis of Compound of Formula (IV)

2,2,3,3-tetrafluoropropan-1-ol (82.88 g, 0.63 mol) was charged to a 250mL round bottom flask fitted with a condenser and dropping funnel. Thealcohol was stirred and heated to 40° C. Sebacoyl chloride (50.05 g,0.21 mol) was charged to a dropping funnel and added slowly to thealcohol. The mixture was stirred at 40° C. for approximately 4 to 5hours, allowed to cool to room temperature and then the excess alcoholwas removed under vacuum. The remaining clear oil was filtered to removeparticulates and then dried over activated molecular sieves. Thereaction gave 60 g (67% yield) of a compound of Formula (IV).

¹H NMR (DMSO): δ 6.38-6.77 (tt, CF₂H), δ 4.53-4.63 (t CH₂), δ 2.37-2.42(t C₂H₄), δ 1.51-1.56 (m C₂H₄), δ 1.25 (s C₄H₈)

¹³C NMR (DMSO): δ 171.77 (s OC═O), δ 117.81 (t CF₂), δ 114.15-114.86 (tCF₂), δ 105.46-112.92 (m CF₂), δ 58.55-59.26 (t CH₂O), δ 32.87 (sCH₂C═O), δ 28.10-28.34 (m C₂H₄), δ 24.10 (s C₂H₄)

¹⁹F NMR (DMSO): δ −50.20-−50.17 (s 4F), δ −64.40-−64.36 (s 4F)

IR: 1756 cm⁻¹ (OC═O), 1108 cm⁻¹ (C—F)

TGA: One mass loss is seen giving a boiling range of 330-350° C.

Density: 1.28 g/ml

Viscosity: 26.33 cP

RPM Centipoise (cP) Torque (%) 2 Out of Range Out of Range 3 25.4 12.7 425.6 17.1 5 25.7 21.4 6 25.7 25.7 10 26.09 43.5 12 26.09 52.2 20 26.3387.8 30 Out of Range Out of RangeSynthesis of 1:1 Combination of Compounds of Formula (V) and (VI)

Sebacoyl chloride (32.66 g, 0.14 mol) and adipoyl chloride (25.00 g,0.14 mol) were charged to a 250 mL round bottom flask fitted with acondenser and dropping funnel. The acid chloride mixture was stirred atroom temperature. 1H, 1H, 5H-Octafluoropentan-1-ol (133.31 g, 0.55 mol)was charged to a dropping funnel and added slowly to the mixture. Themixture was stirred at 40° C. for approximately 7 hours, allowed to coolto room temperature and then the reaction mixture was worked up. Theremaining clear oil was filtered to remove particulates and then driedover activated molecular sieves. The reaction gave 123 g of compounds ofFormula (V) and (VI).

¹H NMR (DMSO): δ 6.85-7.23 (tt, CF₂H), δ 4.73-4.83 (t CH₂), δ 2.38-2.47(m C₂H₄), δ 1.51-1.59 (m C₂H₄), δ 1.24 (s C₄H₈)

¹³C NMR (DMSO): δ 171.54 (s OC═O), δ 171.32 (s OC═O), δ 118.06-117.65 (mCF₂), δ 115.09-113.53 (m CF₂), δ 111.59-110.05 (m CF₂), δ 109.64-107.45(m CF₂), δ 104.11-104.92 (m CF₂) δ 58.16-58.86 (m CH₂O), δ 32.39-33.13(s x2 CH₂C═O), δ 28.01-28.27 (d C₂H₄), 624.07 (s C₂H₄), δ 23.32 (s C₂H₄)

¹⁹F NMR (DMSO): δ −43.64-−43.54 (s 4F), δ −49.62-−49.37 (s 4F), δ−54.46-−54.19 (s 4F), δ −63.09-−62.90 (s 4F)

IR: 1759 cm⁻¹ (OC═O), 1126 cm⁻¹ (C—F)

TGA: One mass loss is seen giving a boiling range of 320 to 365° C. Noimpurities

Density: 1.49 g/mL

Viscosity: 41.04 cP

RPM Centipoise (cP) Torque (%) <2 Out of Range Out of Range 2 39.9 13.33 40.6 20.3 4 40.6 27.1 5 40.6 33.8 6 40.5 40.5 10 41.03 68.4 12 41.0482.1 20 Out of Range Out of Range

The individually made oils (compounds of Formula (V) and (VI)) were thenmixed together in 3 different molar ratios: 1:1, 1:2 and 2:1respectively. Viscosity and density measurements were then performed onall mixtures.

Viscosity Oil mixture RPM Centipoise (cP) Torque (%) Density (g/ml) 1:12 36.0 12.0 1.49 3 36.6 18.3 4 36.4 24.3 5 36.6 30.5 6 36.9 36.9 1037.12 62.0 12 37.74 74.7 1:2 2 35.4 11.8 1.47 3 37.2 18.6 4 36.9 24.6 537.2 31.0 6 37.3 37.3 10 37.37 62.3 12 37.19 74.4 2:1 2 35.4 11.8 1.51 335.8 17.9 4 37.0 24.7 5 36.6 30.5 6 37.0 37.0 10 37.13 61.9 12 37.1974.4Flammability

Selected fluorinated fluids of the invention were tested to assess theirflammability and/or combustibility alone and mixed with fluorocarbonrefrigerant compositions. It was found that the fluorinated speciesexhibited elevated combustion temperature compared to commerciallyavailable polyalkylene glycol (PAG) and polyol ester (POE) lubricantmaterials.

Experimental Method—Hot Manifold Testing

An assessment was made of the ease of ignition of the fluids when incontact with a hot metal surface, using the test apparatus and testmethod as described in ISO Standard ISO 20823:2003. In this testdroplets of the fluid were allowed to fall vertically downwards onto aninternally heated, cylindrical hot surface, inclined at a shallow angleto the horizontal, and which was additionally fitted with a horizontalgutter to trap liquid at one side of the cylindrical body. (The surfaceis hereinafter described as the “manifold”).

The temperature of the manifold was increased stepwise until ignitionwas observed. Observations on the character and vigour of ignition werealso recorded during each test. Five fluids of the invention, two PAGtype lubricants (Nippon Denso ND12 and Daphne FD46XG) and one POElubricant (Emkarate RL68H) were tested. A perfluorinated lubricantmaterial (DuPont Krytox™ GPL150) was also tested as a comparativeexample. The results are tabulated below:

Highest temperature Lowest without temperature ignition with ignitionFluid (° C.) (° C.) Observations Formula (V) 633 643 Immediate ignitionFormula (VI) 608 615 Immediate ignition Formula (VII) 604 615 ImmediateCompound of 626 635 30 s delay before formula (IV) ignition 2:1Combination 636 643 28 s delay before of compounds ignition of Formula(V) and (VI) ND12 (PAG) 438 443 Immediate ignition; burning liquidcollected FD46XG (PAG) 462 467 Immediate ignition; burning liquidcollected RL68H (POE) 628 633 Immediate ignition; gas above tray alsoignited by droplets Krytox GPL150 770 None observed Smoke but no flamein range 600-770° C.

It is evident that the fluids of the invention require significantlyhigher surface temperatures to initiate combustion than those of the PAGfluids. Two of the fluids tested also have ignition temperaturescomparable or higher to that of the POE fluid tested. Both of thesefluids exhibit significantly delayed and less vigorous combustion thanthe POE fluid.

Experimental Method—Testing in Refrigerant Mixtures

The combustion behaviour of mixtures of one of the fluids of theinvention (2:1 combination of compounds of Formula (V) and (VI)) withthe refrigerant fluid 2,3,3,3-tetrafluoropropene (R-1234yf) when incontact with a hot metal surface was investigated. Refrigerant R1234yfis proposed as a suitable fluid for automotive air-conditioning systems,where a leak from the system could result in a spray of refrigerant/oilmixture contacting hot engine surfaces.

The apparatus used comprised an enclosed cubical test chamber, 30 cm ona side, with transparent side and front faces and steel back, top andbottom faces. The two side faces were hinged to provide a means ofpressure relief in the event of an ignition.

A horizontal, hollow, steel cylinder with closed front face, diameter ca75 mm and length ca 70 mm, was mounted onto the steel back face of thechamber with its centre point approximately 160 mm above the base plate.This cylinder was heated on its inside surfaces from outside the testcell by using an oxy-acetylene torch whose flame jet was aimed into thecylinder. Thermocouples were spot-welded into the top and bottom of thecylinder and the heating torch gas rates were adjusted until thetemperatures indicated on each thermocouple were steady and within 10 Kof each other. Additional thermocouples were used to monitor the airtemperature at top, middle and bottom of the test chamber. Once the hotsurface was at steady state, a liquid mixture of refrigerant andlubricant was injected to the test chamber, using a short pipe sectionof Swagelok tubing (6 mm external diameter) as an injection point. Thetube was centrally mounted in the base of the test chamber and protrudedabout 10 mm into the test chamber. This resulted in a vertical spray ofdroplets and vaporised refrigerant entering the chamber, where itsmomentum ensured rapid mixing into the chamber atmosphere. A sketch ofthe test cell is shown in FIG. 1 to illustrate the geometry used.

For each experiment a constant quantity (˜20 grams) of therefrigerant/oil mixture was placed in a feed reservoir vessel, isolatedfrom the chamber by a solenoid valve and initially at lab ambienttemperature (typically from 18 to 20° C.). A standard concentration of3% by weight oil in refrigerant was used. This is typical of the oilcontent in refrigerant circulating in automotive air conditioningsystems.

Video cameras were used to film the release and any subsequent ignitionevents. When the solenoid valve was opened the pressure inside the feedcylinder was monitored as an indication of whether the release hadfinished. The apparatus was monitored for 5 minutes after each injectionfor evidence of flame (visual and by observing the thermocouplereadings). After each injection event an air purge was used to flush thefeed lines and the test chamber before the next injection.

The temperature of the hot surface was progressively increased until anignition event was observed. For each temperature where no ignition wasobserved at least one repeat test was carried out as a check onreproducibility.

It was found that the highest hot surface temperature at which noignition was observed was 818° C. for the combination of R-1234yf withthe combination of compounds of Formula (V) and (VI) fluid. The lowesttemperature at which ignition was observed was 822° C.

A comparative test was made using R-1234yf with PAG lubricant ND12 (alubricant intended for use with R-1234yf refrigerant). It was found thatthe highest hot surface temperature at which no ignition was observedwith this mixture was 795° C. The lowest temperature at which ignitionwas observed was 802° C.

The fluorinated fluid of the invention thus retarded the onset ofignition in this test as compared to the PAG fluid at an equal massloading in the refrigerant.

The invention claimed is:
 1. A composition comprising a heat transferfluid with one or more compounds of formula (II), formula (III), orformula (IV):


2. A composition according to claim 1, wherein the heat transfer fluidfurther comprises one or more compounds selected from the group of(hydro)fluoroolefins (HFOs), hydrofluorocarbons (HFCs),chlorofluorocarbons (CFCs), hydrochlorofluorocarbons (HCFCs) andhydrocarbons, or wherein the heat transfer fluid further comprises oneor more compounds selected from the group of R-1234ze, R-1234yf,R-1233xf, R-1233zd, R-1243zf, R-134a, R-152a, R-32, R-161, R-125, R-134,propane, propylene, carbon dioxide, R-245fa, R-236fa, R-227ea, R-143a,n-butane, iso-butane and R-365mfc, optionally wherein the heat transferfluid further comprises one or more compounds selected from the group ofR-1234ze, R-1234yf, R-1233xf, R-1233zd, R-1243zf, R-134a, R-152a andR-32, or wherein the heat transfer fluid further comprises R-1234ze orR-1234yf.
 3. A composition according to claim 1, which is less flammablethan a composition comprising the same heat transfer fluid combined witha polyalkylene glycol (PAG) and/or polyol ester (POE) based lubricant,or which has an ignition temperature of about 500° C. or greater, orwhich is non-flammable.
 4. A composition according to claim 1 furthercomprising a stabiliser, optionally the stabiliser is selected fromdiene-based compounds, phosphates, phenol compounds and epoxides, andmixtures thereof, optionally comprising an additional flame retardant,and optionally the flame retardant is selected from the group consistingof tri-(2-chloroethyl)-phosphate, (chloropropyl) phosphate,tri-(2,3-dibromopropyl)-phosphate, tri-(1,3-dichloropropyl)-phosphate,diammonium phosphate, various halogenated aromatic compounds, antimonyoxide, aluminium trihydrate, polyvinyl chloride, a fluorinatediodocarbon, a fluorinated bromocarbon, trifluoro iodomethane,perfluoroalkyl amines, bromo-fluoroalkyl amines and mixtures thereof. 5.A heat transfer device containing a composition as defined in claim 1.6. A heat transfer device according to claim 5, which is a refrigerationdevice.
 7. A heat transfer device according to claim 6, which isselected from the group consisting of automotive air conditioningsystems, residential air conditioning systems, commercial airconditioning systems, residential refrigerator systems, residentialfreezer systems, commercial refrigerator systems, commercial freezersystems, chiller air conditioning systems, chiller refrigerationsystems, and commercial or residential heat pump systems, whichoptionally contains a compressor.
 8. A method of retrofitting a heattransfer device comprising the step of removing an existing heattransfer fluid and introducing a composition as defined in claim 1,optionally wherein the heat transfer device is a refrigeration device oran air-conditioning system.
 9. A method of reducing the flammability ofa composition by the addition of one or more compounds of formula (II),(III), or (IV) as defined in claim 1.